Abstract: A travelling precipitate collector in which a transversely travelling frame is movably provided on a longitudinally travelling frame body, striding over a plurality of sedimentation basins and an elevating frame is vertically movably, interposedly provided in a machine frame which is fixed at the transversely travelling frame body and a chain installed with a plurality of buckets is circulated through the machine frame and the elevating frame, and further, a scraper and a pressure detector are installed on the elevating frame.Owing to the above described structures, the travelling precipitate collector can be prevented defects which are caused from the precipitate clinging to a lower portion of the elevating frame and bending moment acting on the elevating frame can be detected and controlled to thereby protect component members.

Abstract: During rough grinding operation of a grinding machine, metal removal rate of the workpiece is detected for shifting the changing point from the rough grinding to fine grinding, and, with larger metal removal rate, the changing point is shifted earlier and vice versa with smaller rate to thereby keep approximately constant fine grinding stock removal to ensure minimum cycle time necessary for grinding work even if the grinding ability of the grinding machine is changed.